If you have a Mac running OS X Mavericks, update 10.9.2 has been pushed to the Mac App Store, which adds several new features, fixes a variety of bugs, and namely fixes the SSL/TLS vulnerability. On the feature side, 10.9.2 adds the ability to initiate and receive FaceTime audio calls, while also blocking individual senders on iMessage. Mail is named as having received a slew of bug fixes: compatibility improvements for Gmail's Archive folder and labels are listed, as well as resolutions for a bug that prevented Mail from receiving messages from "certain providers." The update will require a restart for installation.